As is well known, various processes and catalysts exist for homopolymerization or copolymerization of olefins. For many applications it is of primary importance for a polyolefin to have a high weight average molecular weight while having a relatively narrow molecular weight distribution. A high weight average molecular weight, when accompanied by a narrow molecular weight distribution, provides a polyolefin or an ethylene-.alpha.-olefin copolymer with high strength properties.
U.S. Pat. No. 5,264,504 discloses certain monocyclopentadienyl metal compounds having an amido radical with an aliphatic or alicyclic hydrocarbyl moiety attached thereto through a primary or secondary carbon atom. EPO 416,815 discloses certain monocyclopentadienyl metal compounds which are activated with an alumoxane co-catalyst. U.S. Pat. No. 5,064,802 discloses certain monocyclopentadienyl metal compounds which are activated with a non-coordinating compatible anion of a Bronsted acid salt.